import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: 62536
 * Date: 2024-03-18
 * Time: 21:42
 */
public class UdpEchoServer {
    private DatagramSocket socket = null;

    public UdpEchoServer(int port) throws SocketException {
        socket = new DatagramSocket(port);
    }

    public void start() throws IOException {
        DatagramPacket requestPacket = new DatagramPacket(new byte[4096], 4096);
        socket.receive(requestPacket);

        String request = new String(requestPacket.getData(),0, requestPacket.getLength());

        String response = process(request);
        DatagramPacket responsePacket = new DatagramPacket(response.getBytes(), response.getBytes().length,
                requestPacket.getSocketAddress());
        socket.send(responsePacket);

        // 打印日志
        System.out.printf("[%s:%d] req: %s, resp: %s\n", requestPacket.getAddress().toString(),
                requestPacket.getPort(), request,response);
    }

    public String process(String request) {
        return request;
    }


}
